Overheating gear stick

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Jackle
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Post Fri Jun 17, 2005 12:47 pm

Just driven home along the motorway and noticed that my gearstick gaitor was rather on the warm side, so I pulled it up and felt the actual shaft of the gearstick. Had to take my fingers straight off it was so hot!
Obviously this is not normal, but what would cause it? My thinking is low oil level in the gearbox, but I only changed it a couple of months ago, so unless it's leaked out that "should" be ok.
Is it ok to drive or am I going to be doing damage to the gearbox? Gear changes are still smooth, no changes there.
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bennyp
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Post Fri Jun 17, 2005 12:54 pm

that sounds a bit odd,

my center console heats up a bit on long journeys as that where my exhaust is routed, i suppose that is worth a look?!
Jackle
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Post Fri Jun 17, 2005 1:29 pm

I suppose that's a possibility, it's just that I haven't noticed it before.
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Post Fri Jun 17, 2005 2:15 pm

i would check your gearbox oil mate just to be sure
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Post Fri Jun 17, 2005 3:06 pm

Are you sure no ones lit a fire under your arse :lol:

Did you put the filler plug back in ?
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damian
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Post Fri Jun 17, 2005 7:56 pm

:wink: I read an article in BMWcar Magazine (September 2004; page92/TalkingTech's tip from US BMW Expert Rogue Engineering). The advice states that it is not a good idea to get in the habit of resting your hand on the gearknob of a manual car while driving, as well as using after market shiftknobs (anything over 6 ounces, with the factory knobs being 3 ounces).
I'll quote from the article,
["Within the transmission itself, BMW has a spec of 0.004"-0.006" gap between each gear and the shifter rail in the transmission (for reference, a human hair is approximately 0.0035"). This gap allows for the transmission lubricant to act as a barrier so that the shifter rail and gear are not directly touching, causing premature wear of the gear (not syncros), shifter rail, or both.
"When you make a 0.001" change at the shift knob and maintain pressure (like resting your hand on the shift knob while driving), the required 0.004"-0.006" gap is closed, preventing the lubricant to ride between the gear and the shifter rail. Premature wear of the gear or shifter rail may hamper transmission shifting performance, gear engagement, or worse, require rebuilding or replacement of the transmission...........When considering an aftermarket shift knob, consider how much mass it threatens to add. Too much is a BAD thing fot your transmission!"].
I hope this info was helpful, for more tips visit www.rogueengineering.com.
Jos
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Post Fri Jun 17, 2005 11:16 pm

hmm, that sounds a bit far fetched tbh..

"When you make a 0.001" change at the shift knob and maintain pressure (like resting your hand on the shift knob while driving), the required 0.004"-0.006" gap is closed,"

If you remove 0.001" from 0.006" it's still 0.005" and within the 0.004" - 0.006" range, so why should it make any difference if you keep your hand on it. The gearstick itself has a huge metal ball, that sits on a huge metal plate, thats bolted to the gearbox..

Not doubting Rogue, they do some damn nice stuff, but that sounds a little far fetched to me.

yay getting to use the: :bs:


As to what it could be, best thing is to run the engine/gearstick gets a little warm, then go digging about underneath, see if the gearbox is hot on both sides, check the exhaust heatshield is there. Then you should be able to figure out if its the gearbox directly or not. And do check the oil in the box..
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Jackle
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Post Fri Jun 17, 2005 11:42 pm

Ok thanks guys, my plan of action is to get up early tomorrow and check the oil level before I have to go down the M5 to Exeter. If it's not the oil level I'll have a feel around the gearbox when I get there, if I can.
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randomdave325
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Post Sat Jun 18, 2005 12:00 pm

they do get warm. soon cool down tho. nothing to do with the gearbox. i wouldn't worry about it. check the rubber boot in the shell (under gearbox gaitor) in in one piece. if it worn and holy :jesus: it can let the heat from the exhaust up through as well as excess road noise.
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Post Sat Jun 18, 2005 1:35 pm

So you've never towed a trailer with a '60s Land-Rover then? If you had, you'd know all about hot gearboxes. :lol:

It's just heat soak - the engine's going to be running 90C, and it'll just soak back through the gearbox.
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Jackle
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Post Sat Jun 18, 2005 2:53 pm

I'll try not to worry about it then. It's just I've never really noticed it before, and it does get bloody hot. You can't actually touch the metal gearstick shaft (under the gaitor) for more then a second it's that hot.

Jos, you mentioned about an exhaust heatshield. I had a look under the car this morning when I checked the oil (it was full), and the exhaust goes straight past the gearbox within about a few inches, but there's no shielding between the exhaust and gearbox. Should there be?
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Post Sun Jun 19, 2005 5:38 am

Dude, its is probably cause you have your windows open, this causes the warm air from around the exhaust to get sucked in throught only real hole which is for the gear change assembly etc. due if your interested to the fact that air at speed creates a lower pressure (hence why planes fly and yer footy curves into the top corner) thus the stationary air in your car is at a higher pressure and escapes throught the windows, it is creating a vaccum in your car which is replaced by hot air from the transmission tunnel. close yer windows and make a comparison! (also for you smokers why a partially opened window sucks yer smoke out too!)

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Post Sun Jun 19, 2005 5:51 am

they all get warm...dont think its too much to worry about especially if you've been having some fun, but long trips do it too
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Post Sun Jun 19, 2005 5:41 pm

Think the heatsoak explanation is probably the reason, unless it heats up rapidly? (ie say within 5 miles)

If its a rapid heating its more likely to be friction based-and points to an oil problem in the gearbox-i'd get the oil level checked anyway-just as a precaution
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Jackle
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Post Tue Jun 21, 2005 11:33 am

Well, I've just been out in my old 325 to take my g/f to work, at was a 10 mile round trip and the gearstick didn't warm up at all. The new car would be fairly warm after that.
I've checked the oil level and it was fine. I don't know whether to be worried about it or not. Any more ideas?